CN101795467A - Wireless micropower network positioning system and positioning method thereof - Google Patents
Wireless micropower network positioning system and positioning method thereof Download PDFInfo
- Publication number
- CN101795467A CN101795467A CN200910259930A CN200910259930A CN101795467A CN 101795467 A CN101795467 A CN 101795467A CN 200910259930 A CN200910259930 A CN 200910259930A CN 200910259930 A CN200910259930 A CN 200910259930A CN 101795467 A CN101795467 A CN 101795467A
- Authority
- CN
- China
- Prior art keywords
- moving target
- network
- network node
- power
- signal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Landscapes
- Position Fixing By Use Of Radio Waves (AREA)
- Mobile Radio Communication Systems (AREA)
Abstract
The invention relates to positioning technology, in particular to a wireless micropower network positioning system and a positioning method thereof. The invention overcomes the defects that the conventional positioning system has complex structure, high investment and high running cost, and cannot meet the requirements of various kinds of practical application under complex environment conditions such as cities and the like, and discloses the wireless micropower network positioning system and the positioning method thereof. The position of a moving target is determined by taking the position of a network node as a reference according to the general relationship among a signal source, a receiver, transmitting power and signal intensity in a positioning area and the specific relationship depending on environmental characteristics. The positioning system has the advantages of simple structure, low cost, mature technology, no need of complex measurement and calculation, and no need of an electronic map to meet the requirements of practical application; and the positioning system is a positioning network, and is also a communication network capable of transmitting position information and control information, so that the structure of the system is simplified, the system is convenient to use, and the running cost is greatly reduced.
Description
The application is that application number is 200610022177.7, the applying date is on November 2nd, 2006, denomination of invention is divided an application for the Chinese patent application of " wireless micro-power network positioning system and localization method thereof ".
Technical field
The present invention relates to location technology, particularly a kind of wireless micro-power network location technology and localization method thereof.
Background technology
Up to the present location technology all is the method for the wireless signal location of employing.Existing navigation system can be divided into basically with GPS and is the navigation system of representative and is wireless network (comprising GSM, the cdma network) navigation system of representative with the mobile communications network.
The GPS location technology:
The GPS receiving terminal of object by being attached thereto that be positioned receives the framing signal of four (at least three) gps satellites emissions simultaneously, and (X, Y Z) realize the location to calculate residing longitude and latitude of this object and height coordinate.This X, Y, the Z location coordinate information in general practical application, must be used with electronic chart, and, need be converted to the geographical location information that we are familiar with toward contact, street name for example, concrete reference location etc. could real convenient use.To moving target, for example during vehicle location, also need calculating positional information, by existing mobile communications network, pass to control centre, could the real purpose that arrives the location---to management of vehicles, monitoring.With regard to the moving target location, the GPS navigation system needs gps satellite, GPS receiver, mobile communications network, mobile communication terminal (GMS or CDMA transceiver module) and control centre to realize at least.The shortcoming of GPS navigation system, except the cost and operation cost height of setting up navigation system (comprising mobile network's usage charges), its use also is subjected to great restriction in the city.Because use one of important prerequisite of GPS equipment, be that the direct projection path is arranged between GPS receiver and the satellite, and gps signal exist signal to receive the blind area at building intensive city and interior of building.The GPS location also will be subjected to the influence of multipath effect and many other factors in addition, comprises that long grade of initial alignment signal capture time (is generally 0.5～15min).Field experiment shows, in built-up city, the public transit vehicle of GPS receiver is installed, and the probability that can normally receive the GPS framing signal is approximately about 70%.At some special occasions, as in the concrete steel building, in basement or the mine, then can not receive gps signal fully.
The mobile communications network location technology:
Location technology based on mobile communications network, except will be to existing mobile network's layout, the software and hardware of network base station and portable terminal is made outside the bigger change, and its use also will be subjected to the very big influence of factors such as non-line-of-sight propagation in the city, multipath effect and multiple access interference.In network topology, generally require portable terminal, can be simultaneously and 3 or 3 above base stations, carry out direct communication, by the range finding of various complexity, the position that portable terminal is determined in direction finding.And existing mobile communications network, what mainly consider is voice communication, thereby, be difficult to satisfy the requirement of location.
In sum, the major defect of existing location technology and method is, complex structure, and investment is big, and the running cost height can not be in the city, or works under the complex environment condition such as down-hole, mine, thereby can not satisfy the needs of many practical applications.
Summary of the invention
Technical problem to be solved by this invention is exactly at existing navigation system complex structure, cost height, the running cost height, the shortcoming that use occasion is limited provides a kind of GPS of not relying on and existing mobile communications network, wireless micro-power network positioning system and localization method thereof.
The present invention solves its technical problem, the technical scheme that adopts is: have the fixed position by setting up one by several, the network that the wireless micro-power transceiver that can communicate with control centre's computer is formed, and be installed in wireless micro-power transceiver on the movable object that needs the location, the wireless micro-power network positioning system of forming, utilize the transmitting power of the transceiver of network node and movable object, relation between receiving sensitivity and received signal intensity and the transmission range, utilize known location of network nodes again, realize location movable object; And utilize same network, realize the transmission of movable object positional information and other control information.
Each has the wireless micro-power transceiver of fixed position in the network, is called as a network node, is installed in the wireless micro-power transceiver on the movable object that needs the location, is called as moving target; Multiple modes such as described network node is connected with control centre with transmission information by wired or wireless mode, and its connected mode can adopt starlike, and is tree-shaped, netted; The computer system of described network and control centre links; Be connected by communication between described network node and the moving target; Described computer system stores has the address of network node, the identity identification information of moving target and the network management software; Described transceiver is made of the integrated circuit (IC) chip with complete wireless transmission and receiving function, and they also can only have the single wireless transmission or the function of reception, and their transmitting power satisfies the relevant regulations restriction of local government; When described network was the Zigbee network, these network nodes were exactly the FFD of Zigbee network; Moving target is exactly the RFD of Zigbee network.
Adopt the localization method of above-mentioned wireless micro-power network positioning system to have following several:
First kind of localization method is called the geometric center positioning mode:
Set up writing to each other of network node and moving target, with the geometric center of receiving the strongest 1-3 of a moving target signal network node position as moving target;
Moving target signal described here, can be moving target self folk prescription to the identity code signal that sends, also can be after moving target is received the call signal of system, return to the back-signalling of network node.
Here need to prove, the call response signal is different from the signal that moving target self sends, the two difference is: the latter only depends on that can network node receive the signal of moving target, it is that a kind of folk prescription is to communication, and the former can receive before the call response signal of moving target at network node, at first moving target wants to receive the call signal from network node, and it is a kind of two-way communication process.
Second kind of localization method: signal strength signal intensity method
It is to utilize in given locating area, the received signal strength signal intensity of setting up by field measurement of wireless receiver in advance, with general relationship to the signal source distance, the signal strength signal intensity from moving target (or network node) that receives by Measurement Network node (or moving target) is determined the distance between moving target and the network node again;
The third localization method: search method
It is to utilize in given locating area, the wireless receiver of setting up by field measurement leaves the distance of signal source in advance, general relationship with the critical transmitting power of signal source, the critical transmitting power here, be meant that wireless receiver is at given distance and position place, in the time of can receiving the signal source signal, the signal source minimum emissive power that must have, again by changing the transmitting power of network node (or moving target), find out critical transmitting power, determine the distance between moving target and the network node corresponding to place, moving target (or network node) position;
The 4th kind of localization method: fingerprint technique
It comprises the signal strength signal intensity fingerprint technique, and critical transmitting power fingerprint technique.This method does not rely on signal source transmitting power or radio-frequency (RF) signal strength, and the general relationship between the distance, but depend in this locating area, be in the signal source and the transmitting power thereof of certain particular location, and existing between the signal strength signal intensity at diverse location place in the zone, the special relationship of certain environmental conditions in this zone that places one's entire reliance upon.
Signal strength signal intensity fingerprint technique: set up writing to each other of network node and moving target, utilization is measured on J network node, one group of signal strength values from same moving target, the signal strength signal intensity fingerprint characteristic of forming, with stored by field measurement in advance in the database, the unlike signal intensity fingerprint characteristic of J network node is with the one-to-one relationship of moving target diverse location; Or utilize the one group of signal strength values measure at the moving target place from J network node, the common signal strength signal intensity fingerprint characteristic of forming, with stored by field measurement in advance in the database, corresponding to this J network node, the unlike signal intensity fingerprint characteristic of moving target, with the one-to-one relationship of moving target, determine the particular location of moving target, wherein J 〉=1 at diverse location.
Critical transmitting power fingerprint technique: set up writing to each other of network node and moving target, by changing the transmitting power of network node or moving target, find out corresponding to same moving target position, one group of fingerprint characteristic that critical transmitting power is formed of Q network node, or with respect to this Q network node, the one group of critical transmission power level that records at the moving target place, the fingerprint characteristic of forming, with store by field measurement in advance in the database, different critical transmitting power fingerprint characteristic, with the one-to-one relationship of moving target, determine the position of moving target, wherein Q 〉=1 at diverse location.
In above the third " search method " and the 4th kind " fingerprint technique ", all use the notion of critical transmitting power.In fact it is exactly a process of searching moving target.It utilizes the transmitting power that changes network node or moving target, change between network node and the moving target, can realize the scope of two-way or one-way communication, by finding out the change point that can receive between the two to square signal, find out corresponding critical transmitting power, thereby hunt out the position of moving target.Because general micropower single-chip transceiver all have the function of multistage transmitting power control, thereby we can be passed through control command easily, change the transmitting power of moving target or network node, thereby reaches the purpose of searching moving target.
Use the notion of critical transmitting power to locate, locate similar with the notion of using signal strength signal intensity, the universal law of all having utilized signal strength signal intensity to decay with distance, but locate with respect to the notion of using signal strength signal intensity, use critical transmitting power to locate, has conspicuous superiority: at first, when the notion of using signal strength signal intensity is located, in your the measured signal strength signal intensity, comprised that many and location purpose are irrelevant, from the contribution of other signal sources, they be divided and come, very difficult sometimes; Secondly, field measurement shows, the measurement of signal strength signal intensity has suitable difficulty, and this mainly is meant the stability and the accuracy of signal when measuring; At last, because general transceiver does not often have the signal strength signal intensity deixis, thereby the method for using the notion of signal strength signal intensity to locate, also just be subjected to great limitation.And use the method for critical transmitting power, then there are not these problems.
The invention has the beneficial effects as follows simple in structurely, easy to use, cost is low, technology maturation.The present invention does not need complicated measurements and calculations, can not need electronic chart yet, just can satisfy the actual location needs; System itself is a fixer network, is again a communication network that can carry out message transmission, thus can collect the location and message transmission be one, not only made things convenient for practical application, but also greatly reduced operation cost.
Description of drawings
Fig. 1 is that system of the present invention forms schematic diagram;
Fig. 2 is signal strength signal intensity and the schematic diagram that concerns that leaves the signal source distance;
Fig. 3 is the signal covering radius schematic diagram of transmitting set;
Fig. 4 is the location radii schematic diagram of wireless receiver;
Fig. 5 is the schematic diagram of 1 network node position as moving target position;
Fig. 6 is the schematic diagram of the geometric center of 2 network node positions as moving target position;
Fig. 7 is the schematic diagram of the geometric center of 3 network node positions as moving target position;
Fig. 8 is a schematic diagram of determining moving target position according to the distance of moving target to 3 network node that calculates;
Fig. 9 is critical transmitting power schematic diagram, Q 〉=Qm, and M can receive the signal of O, and Q＜Qm, M do not receive the signal of O;
Figure 10 is corresponding same moving target position, the different critical transmitting power of heterogeneous networks node;
Figure 11 is the position of corresponding heterogeneous networks node, in the different critical transmitting power of the moving target of certain particular location;
Figure 12 is Ta, and Tb, Tc form the signal strength signal intensity fingerprint schematic diagram of moving target at position O;
Figure 13 is Qa, and Qb, Qc form the critical transmitting power received signals fingerprint schematic diagram of moving target at position O.
Embodiment
Below in conjunction with drawings and Examples, describe technical scheme of the present invention in detail.
For ease of understanding technical scheme of the present invention, earlier the several notions relevant with the present invention simply are described below:
The transmission of wireless signal:
Under ideal conditions, transmitting set is by the outside radiofrequency signal of the certain power of emission of antenna, near the radio-frequency (RF) signal strength of certain point transmitting set, with this point apart from square being inversely proportional to of the distance of transmitting antenna, we can use formula: Tr=KQ/R
2Represent.Here Tr representative is apart from the signal strength signal intensity at transmitting set R place, and Q represents the signal strength signal intensity of transmitting set antenna end, and K then can simply be thought of as attenuation coefficient.In actual applications, the size of actual signal intensity and the relation of leaving the signal source distance, because signal transmission environment condition and ideal situation have bigger difference, thereby, also just can not represent with top formula simply, but for convenience's sake, people still like the form with formula above using, and express this relation, only the index in the formula " 2 ", need to use a unknown number " x " to replace, promptly formula changes Tr=KQ/R into
x, because signal strength signal intensity with the variation of distance, generally all be the weak relation of a kind of monotone decreasing, thereby " K " and " x " can obtain in the formula by simple actual field measurement.(Fig. 2)
For a given transmission environment and given network node and moving target, we can be by the numerical value of several groups of signal strength signal intensities of actual measurement and distance at the scene, obtains the value of K and index x in the formula, more to meet on-site actual situations.If changes in environmental conditions is little in the locating area, we can be with in the locating area, and in the position of a representative transmission environment, measured K and the value of x are used for whole locating area.For some bigger place of transmission of wireless signals condition difference, then need to carry out actual measurement in these places specially, to obtain being specially adapted for these local computing formula.The computing formula of utilizing us to set up by field measurement just can be utilized aforesaid method at an easy rate, and moving target has been positioned.
The signal covering radius Rab of transmitting set:
Can wireless receiver B receive that another is separated by a distance, the signal that the transmitting set A of use same channel is launched, both depended on that signal that transmitting set A launched arrives the signal strength signal intensity Tb at wireless receiver B place, also depended on the receiving sensitivity Brs of wireless receiver B.As Tb during greater than Brs, B just can receive the signal of A.We are the signal strength signal intensity of certain position of distance A, and the distance R ab when just equaling the receiving sensitivity Brs of wireless receiver B is called the signal covering radius of A corresponding to wireless receiver B.Rab is with the reduction of the transmitting power of A, or the reduction of the receiving sensitivity of B and reducing.(Fig. 3)
Location radii Rba:
When the fixed-site of A, the transmitting power of A and the receiving sensitivity of B one regularly, it is the center of circle with A that B has only when being in one, Rab is in the fixed range of radius the time, just can receive the signal of A.Otherwise with the fixed-site of B, then having only when A enters into one is the center of circle with B, and Rab is in the fixed range of radius the time, and B just can receive the signal of A.Signal covering radius and location radii are same thing in essence, and only the former is the center with the transmitting set, and the latter is the center with the wireless receiver.(Fig. 4)
Critical transmitting power:
Critical transmitting power is meant two transmitting sets separated by a distance and receiver, when wireless receiver can receive the signal of transmitting set, and the minimum emissive power that transmitting set must have.Must be noted that: at opening, the distance that wireless receiver leaves transmitting set is far away more, the critical transmitting power of transmitting set is just big more, but in the complicated transmission environment that has building etc., owing to block, the reason of reflection and multipath transmission, this relation is then not necessarily always set up.(Fig. 9)
Received signals fingerprint:
At zone with a varied topography or interior of building, radio signal transmission has dependence to landform and communication barriers thing, thereby presents very strong receiving station particularity.Therefore for each acceptance point, the multipath structure of this channel is only to each position.If a radiofrequency signal emits from some positions, we are in the received signal strength signal intensity of different receiving positions, to no longer defer to signal strength signal intensity with leaving the signal source distance universal law of decay gradually, and will present a kind of dependence this distinctive transmission environment in zone.Utilize this particularity, we can use at several receiving stations and record, and from one group of signal strength values of the signal source of same position, form the fingerprint characteristic of this source location, next corresponding with the position at signal source place, set up a kind of relation one to one.(Figure 12)
Set up the required fingerprint characteristic of this one-to-one relationship, should form by the signal strength signal intensity of what receiving stations actually, depend on the environment of actual location.For example, to coal mine down-hole personnel location, or the purpose of the public transit vehicle location that certain circuit along the city is travelled, 1-2 website of general selection is just enough, for other position application, select three receiving stations, generally should also just can set up and thisly concerned one to one.
If we pass through field measurement in advance, set up the diverse location of moving target in locating area, with relation one to one between the signal strength signal intensity fingerprint characteristic of its corresponding receiving station, and deposit database in, we just can utilize the signal strength signal intensity fingerprint characteristic that measures at corresponding website conversely, compare with the database of fingerprint feature, thereby find out the position of corresponding moving target, realize location moving target.
In order to be implemented under the complex environment the location of moving target, we not only can use at several receiving stations place, and one group of signal strength signal intensity fingerprint that the measured signal strength signal intensity from same moving target is formed is with the corresponding relation of moving target particular location; We can also use at same moving target position place, and one group of signal strength signal intensity fingerprint characteristic that the measured unlike signal intensity from several network nodes is formed is with the corresponding relation of moving target particular location; Same reason, we can also use the position corresponding to same moving target, the critical transmission power level that several network nodes are different, one group of critical transmitting power fingerprint characteristic being formed, with the corresponding relation of moving target particular location, or corresponding to the several network nodes that are in diverse location, the different critical transmission power level of moving target, one group of received signals fingerprint feature being formed is with the corresponding relation of moving target particular location.(Figure 13)
Communication distance between two transceivers:
Communication between two transceivers, the difference that has directivity, network node transmits, moving target receives this signal (up), transmit with same moving target, same network node receives this signal (descending), be two diverse communication directions, be complete different two things: because network node transmits, communication distance during the moving target received signal, only depend on the transmitting power of network node and the receiving sensitivity of moving target, and have nothing to do that vice versa with the receiving sensitivity of network node and the transmitting power of moving target.This is as dialogue between you two of me, and your hearing is good, and mine is loud, and you can hear my voice in far place, otherwise if my hearing is poor, your sound is also little, and I just can only just can hear your sound in very near place.Thereby the network node that discusses previously is in emission, and moving target is in reception, moving target is in emission conversely, it is two diverse states that network node is in reception, and the signal strength signal intensity that they are involved, critical transmitting power are also just different certainly.Unless transmitting power between the two and receiving sensitivity all do not have difference.
Navigation system:
Navigation system is by network node, and the computer system of moving target and control centre is formed.For the moving target of given transmitting power, the location radii of network node, only, relevant with the transmitting power of moving target with the receiving sensitivity of network node; Equally, the signal covering radius of network node, only, relevant with the receiving sensitivity of moving target with the transmitting power of network node.Thereby we can pass through to adjust the transmitting power of moving target, or change the receiving sensitivity of network node, change the size of network node location radii; We also can pass through to adjust the transmitting power of network node, or change the receiving sensitivity of moving target, change the size of network node signal covering radius.
Can moving target receive the call signal of network node, depends on whether moving target is in the signal covering radius of network node; And network node will be able to be received the calling return signal that moving target is beamed back, and then moving target is at first wanted to receive the call signal that network node sends.Thereby, for given moving target, this had both depended on the size of the signal covering radius of network node, the size that also depends on the location radii of network node, in other words, have only the distance between moving target and the network node, all want hour than in these two radiuses any one, network node may receive that just moving target beams back the call response signal that comes.
Like this, in moving target is in the network node location radii, we are by changing the transmitting power of network node, when changing the signal covering radius of network node, can receive the variation of call response RST from network node, can find out the critical transmitting power when this taking place changing, and corresponding signal covering radius, this signal covering radius is exactly a moving target and the distance of corresponding network node.
Some some areas in orientation range, environmental condition possibility more complicated, at this moment, by increasing the density of network node, dwindle the location radii of network node, or the method for signal covering radius, or adopt the received signals fingerprint positioning mode can reach the purpose that improves positioning accuracy.
Here it should be noted that influences wireless communication distance, and except the receiving sensitivity of the transmitting power of signal source and wireless receiver, the height and position of signal source and wireless receiver also has very big influence.Thereby, in navigation system, should note the height and position of moving target and network node, should be consistent as much as possible.
The wireless micro-power communication network:
Here said wireless micro-power communication network is all wireless micro-power communication networks that comprise the Zigbee network.Be the transmitting power of this network of network node and moving target, all meet the scope of the micropower transceiver of national defined in principle, only under individual cases,, the transmitting power of network node suitably can be improved according to the actual needs of network service; Secondly, the bind mode of network node can be wired in this network, and for example the bind mode of most of base station of mobile communication network is also wireless, for example the bind mode of Zigbee network.They have, and general communication network has, and can transmit the function of information in network, and they can have different information transmission modes and agreement.Need to prove, our localization method as described herein, it also is applicable to general wireless communication network system, for example existing mobile communication network is convenient simple when only it being used for wireless micro-power network.
The Zigbee network:
Zigbee is a kind of new wireless network communication standards, is that purpose is formulated for industrial and home automation mainly.Characteristics are low-cost, low-power consumption, low data bulk and high integration.Itself is an information transmission network, it to be used as a fixer network, we only need be with the host node FFD in the Zigbee network system (global function device) as the network node in the navigation system, and network child node RFD (simplification functional device) is as portable terminal; Simultaneously, we also need the needs according to actual location, adjust the transmitting power of host node and child node, comprise receiving sensitivity in case of necessity, so that the communication range of network node and positioning accuracy can both satisfy the needs of practical application.Use the Zigbee network as navigation system, generally speaking, require to have fixing position as the FFD of network node.
Moving target:
Be meant by the entrained micropower transceiver of the object that is positioned (it can be personnel, vehicle or other object that can move).
System configuration of the present invention and localization method thereof:
System configuration of the present invention as shown in Figure 1.Moving target M emission, the framing signal that includes moving target M identity information, received by certain or some network nodes, this or these network node, again with address information own, and the identity code information of the moving target that is received, information (if necessary) such as signal strength information or transmitting power size, be sent to control centre, control centre is according to these information and obtain by field measurement in advance, be stored in other related data in control centre's computer, with this location of network nodes, or the geometric center of these network node positions, or the position that calculates by aforesaid localization method, as the position of moving target, thereby finish location to moving target.
Between network node and the network node, and communicating by letter between network node and the control centre, can adopt wire communication, also can adopt radio communication.
Embodiment
Need at first to determine positioned area, positioning accuracy and the localization method that need adopt, again according to localization method and positioning accuracy request, set up wireless micro-power communication network (also can utilize existing cordless communication network), whole locating area is carried out signal cover, whole topology of networks can be various, starlike, tree-shaped, netted etc.Under special circumstances, also can adopt the website of compartment to cover, personnel positioning point in the tunnel under the fixed line of public transit vehicle operation, the coal mine for example, the monitoring station on the highway etc.Each network node should be set up corresponding station location marker, and the layout of network node should be consistent with the localization method of concrete employing.
All moving targets that need locate that are in the network are identified, and the wireless micro-power transceiver is installed, generally speaking, the setting that is used for all wireless micro-power transceivers of moving target should be in full accord.
When use needed method that signal strength signal intensity locatees, fixer network node or moving target also should possess and have, the function (RSSI) of received signal intensity indication.
When needs used the method for critical transmitting power to position, moving target or network node should have the function of transmitting power size control classification.
Carry out concrete description with regard to aforementioned four kinds of localization methods respectively below us:
1. simple to system, under the not high situation of required precision, can use the geometric center positioning mode, determine the position of moving target:
At first set up writing to each other of network node and moving target:
When the framing signal of moving target M emission is only received by a certain network node A, mean that it is the center of circle that M is in A, radius is a=(KQ/Tr)
1/xScope in, as shown in Figure 5.At this moment, the position of this network node A is exactly the position of moving target M.As can be seen, the transmitting power of moving target M receiving sensitivity more little or network node A is low more, and then this radius a is more little, and the physical location of moving target M is just more near network node A, and positioning accuracy is also just high more.This situation is fit to equally to receive the strongest network node of framing signal, as the localization method of moving target position.
Fig. 6 shows the situation of 2 node locating.Node A and B have received the framing signal of moving target M simultaneously among the figure, and perhaps the framing signal intensity on node A, the B is greater than the framing signal intensity on other node.At this moment we are with the geometric center of node A, B---and the mid point of node A, B line is as moving target M position.
Fig. 7 is the situation of 3 node locating, and node A, B, C have received the framing signal of moving target M simultaneously among the figure, and perhaps the framing signal intensity on node A, B, the C is greater than the framing signal intensity on other nodes.At this moment we are with the geometric center of node A, B, C---and be the position of the intersection point of three center lines of △ ABC as moving target M.
Utilize this method, we can utilize existing mobile communication network at an easy rate, determine the position of portable terminal self, as long as we increase a function in existing mobile radio communication, promptly when the mobile subscriber need know the Position Approximate of self, by the mobile phone location button, send when location information request is provided to the mobile communication system of correspondence, note will be passed through near base station, respond the more specific location information of this base station, (for example, " your present position is xx district; near the xx landmark etc.; ... ..) then the cellphone subscriber just can be used as this position own position, if near have several base stations to communicate by letter with it, we just can obtain near the positional information of several base stations; the top localization method that we are said of utilization, the cellphone subscriber just can know the position of oneself more clearlyly.Because the distance between the general PHS base station is closer, thereby this method is for the Personal Handyphone System system, resulting positional information should have certain practical value.
2. at the simple relatively locating area of transmission environment, when we have higher the requirement to the positioning accuracy of moving target, we can use signal strength signal intensity method or search method: when using this method, need in advance by on-the-spot simple actual measurement, set up in the locating area, signal strength signal intensity with leave the relation of signal source distance, or the relation of critical transmitting power and receiving range, or find out the value of K and x in the aforementioned computing formula.In actual applications, except that indivedual radio signal transmission environment compared the special networks node, we can be used for other network node in the locating area with the measured result of a representative network node.Utilize this measured result relation, control centre just can utilize aforesaid signal strength signal intensity method, or search method has calculated the distance between moving target and the network node.
Signal strength signal intensity method: according to the received signal strength signal intensity of some network nodes from moving target, or the received signal strength signal intensity of moving target from this network node, utilization is set up through field measurement in advance, received signal intensity and to the relation of corresponding signal source distance just can calculate the actual range between this network node and the corresponding moving target.Adopt in the same way, we can calculate same moving target respectively to the distance between the heterogeneous networks node, utilize the position coordinates of these network nodes itself again, calculate the position coordinates of moving target.(Fig. 8)
Search method, this method be again in two kinds of situation:
1) locate by the transmitting power that changes network node: certain moving target is in certain position in the locating area, around this moving target, there be n network node (Figure 10), this n network node can both receive the signal that moving target is sent, when this moving target of calling network, as long as this moving target can receive the call signal from network node, this n network node one receives the back-signalling of this moving target surely.The distance of they and moving target is respectively, L1, and＜L2,＜L3 ...＜Ln (the distance L n of n network node and moving target is farthest).Suppose when these network nodes use certain identical transmitting power to call out moving target, moving target can receive the call signal from all this n network nodes, but call out the progressively reduction of transmitting power along with this this, a little less than the received call signal from this n network node of moving target will become more and more, when the transmitting power of network node just has been lower than Pn, moving target will at first not receive the call signal from n network node, and n network node also just can not receive the back-signalling from moving target naturally.At this moment, Pn is exactly the critical transmitting power of n network node corresponding to this moving target, when Ln is exactly network node use Pn transmitting power, maximum distance when moving target can receive n node signal, it also is that n network node is when transmitting power is Pn, corresponding to the signal covering radius of this moving target.Utilization is set up through field measurement in advance, the critical transmitting power of network node and the relation that arrives the moving target distance, and we are easy to calculate the actual range of moving target to this network node.
Along with the network node transmitting power further reduces, moving target will can not receive one by one from n-1, n-2 ... .3, the signal of 2,1 network nodes, these network nodes just do not receive the back-signalling of moving target one by one yet equally.Like this, we will obtain corresponding n successively, n-1 ... ..3, the critical transmitting power of 2,1 network nodes, Pn-1 ... ..P3, P2, P1 and calculate the distance of moving target to the corresponding network node.Equally, when the transmitting power of network node from minimum, when progressively increasing, we can obtain identical result, only this moment, the direction of whole process is fully opposite, i.e. these network nodes, to begin to receive the back-signalling that moving target is sent one by one from leaving the nearest network node of moving target.When actual location, we often only need to determine the distance of moving target to 1-3 nearest network node, just are enough to satisfy the requirement of actual location, for example the public transit vehicle on the urban public bus lines is located and coal mine under personnel positioning etc. in the tunnel.
2) locate by the transmitting power that changes moving target: certain moving target is in certain position in the locating area, around this moving target, m network node (Figure 11) arranged, be respectively with its distance, H1,＜H2,＜H3 ... (the distance H m of m network node and moving target is farthest for＜Hm.When moving target adopted maximum power transmission, this m network node can both be received the signal of sending of moving target.If we reduce the transmitting power of moving target from big to small one by one, a little less than the received signal from moving target of this m network node will become more and more.When the transmitting power of moving target during, leave moving target m network node farthest and at first do not receive signal from this moving target just less than Qm.At this moment, Qm is exactly the critical transmitting power of this moving target corresponding to m network node, Hm is exactly that moving target is when transmitting power is Qm, m network node can receive the maximum distance of this moving target signal, also be that moving target is when transmitting power is Qm, corresponding to the signal covering radius of m network node.Utilize in advance through field measurement and set up, the critical transmitting power of moving target and relation to corresponding network node distance, we are easy to calculate the actual range that moving target arrives this network node.
Along with the moving target transmitting power further reduces, network node is from as far as the signal that closely can not receive one by one from moving target, like this, we will obtain successively corresponding to heterogeneous networks node Hm-1 ... ..H3, H2, the critical transmitting power Qm-1 of H1 ... ..Q3, Q2, Q1 and calculate the distance of moving target to the corresponding network node.Equally, when our transmitting power from minimum, when progressively increasing transmitting power, we can obtain identical result, only this moment, whole process direction is fully opposite, i.e. these network nodes, to begin to receive the signal that moving target is sent one by one from leaving the nearest network node of moving target.With the front discuss the same, when actual location, we often only need definite nearest from moving target, 1-3 network node just is enough to satisfy the needs of actual location to the distance of moving target.
Here also have a kind of applicable cases, in this case, we only need to allow moving target know self residing position just ourselves.At this moment, we can be by changing the transmitting power of moving target, and peripherad network node sends call signal, and require network node to give to respond.For example, be in the mobile communication terminal in cordless communication network (Personal Handyphone System, WLAN, networks such as the Zigbee) signal cover, call signal is sent in peripherad base station, and request gives to respond.At this moment, if, moving target self wants to receive the back-signalling of network node, then network node at first must receive the call signal of moving target, thereby, by changing the transmitting power of moving target from big to small or from small to large, we can obtain easily, critical transmitting power corresponding to the moving target of heterogeneous networks node, utilize the physical location of these network nodes again, thereby obtain the actual range (distance of wireless communications network base station and portable terminal) between moving target and the network node.When actual location, we often only need know the distance of 1-3 network node to moving target, just are enough to satisfy the needs of actual location.Obviously, from 1-3 nearest network node of moving target, be undoubtedly best choice.If we can be in above various wireless communication network base station, increase is specifically designed to the location, respond relevant functions such as mobile terminal calling, we just can be easy to realize utilizing above various cordless communication networks, determine the purpose of portable terminal self-position.
3. very complicated at the locating area environment, and the very high application scenario of positioning accuracy request, we can adopt the received signals fingerprint positioning mode: the received signals fingerprint positioning mode comprises signal strength signal intensity fingerprint positioning mode, with critical transmitting power fingerprint positioning mode, the received signals fingerprint positioning mode does not also rely on received signal intensity, transmitting power with signal source, or the universal law between the receiving range, for example aforesaid computing formula, but depend in this locating area, be in the transmitting power of the signal source of certain particular location, and existing between the signal strength signal intensity at interior diverse location place, zone, the special relationship of certain environmental conditions in this zone that places one's entire reliance upon.
Specific practice is: set up writing to each other of network node and moving target, in the needs positioned area, for moving target each position in locating area, by on a plurality of network nodes adjacent with moving target, measure one group of signal strength values simultaneously, or the one group critical transmission power level corresponding with this position, or corresponding to these heterogeneous networks nodes, one group of critical transmission power level of this moving target, set up moving target each particular location in locating area, corresponding with the unlike signal fingerprint localization method that is adopted, the received signals fingerprint property data base.
Signal strength signal intensity fingerprint positioning mode: set up writing to each other of network node and moving target, utilization is on J network node, receive different signal strength signal intensity simultaneously from same moving target, the common signal strength signal intensity fingerprint characteristic that forms, with the unlike signal intensity fingerprint characteristic that stores in advance in the database, with the one-to-one relationship of the different particular locations of moving target, determine the position of moving target, wherein J 〉=1.
Critical transmitting power fingerprint positioning mode: set up writing to each other of network node and moving target, utilization records on Q network node, one group of critical transmission power level (or moving target is with respect to one group of critical transmission power level of this Q network node) corresponding to certain particular location of moving target, the common critical transmitting power fingerprint characteristic that forms, with the different critical transmitting power fingerprint characteristic that stores in advance in the database, one-to-one relationship with the different particular locations of moving target, determine the particular location of moving target, wherein Q 〉=1.
The composition of navigation system of the present invention and each several part function:
Navigation system of the present invention by the network node that the wireless micro-power transceiver with constant mark position constitutes, is equipped with the moving target of wireless micro-power transceiver, control centre's computer, and the network management software is formed.Between network node and the moving target, can carry out radio communication.For example, moving target can have the framing signal of self identification sign indicating number to the network node emission, also can receive other signal from network node; Network node and moving target, it can be the wireless micro-power transmitter that only has single emission function, or only has a wireless micro-power receiver of single receiving function, they can have received signal intensity Presentation Function, or transmitting power controlled function, the concrete localization method that is adopted is depended in concrete functional requirement.
Described network node all links by wired or wireless communication mode and control centre's computer.Network node is a position reference point in navigation system, also is the relay of a network service.
The described network management software is used to manage between moving target and the network node, between network node and the network node, and the message transmission between they and the control centre's computer;
Described control centre computer is used for operational network management software and located in connection Signal Processing.
Navigation system of the present invention can have simultaneously to moving target location and function that moving target position information and other control and management information are transmitted on whole micropower communication network.
Superiority of this navigation system and economic results in society:
The present invention is simple in structure, and technology maturation is economical and practical.The market price that constitutes the native system network node is no more than 600 yuan, and the market price of moving target is no more than 100 yuan of RMB, (and the cost of an existing mobile communication base station is generally all about 1,000,000 yuan); The transmitting power of network node and moving target can be from 0.01 milliwatt, and to 100 milliwatts or bigger, positioning accuracy can be from several meters to hundreds of rice.
Because network node is with low cost, this navigation system network node spacing can be done very closely, even can accomplish the node in each room, like this, just will have that mobile communications network must face now, complicated inhomogeneous signal transmission environment in the large coverage becomes simple relatively environment uniformly in the little coverage, has improved positioning accuracy simultaneously greatly.
This navigation system module integrated level height, reliable operation, volume is little, and power consumption is little, and is flexible for installation, easy to maintenance.In addition, it can also be directly embedded in the device systems, thereby uses very convenient.
This navigation system, both integrate, thereby greatly reduce navigation system construction cost and operation cost for localization part (GPS) that existing GPS locating and monitoring system is included and signal hop (existing mobile communications network).Thereby the present invention can solve in city and other numerous areas actual location problem (for example public transit vehicle is located, coal mine down-hole personnel location etc.) that many urgency are to be solved effectively with extremely low cost.
The application example explanation:
We turn to example with the intelligence of a public bus network in the city and are illustrated:
On the traffic lights bar of whole public bus network each crossroad central authorities along the line, or on other electric pole, and the terminus of public bus network, network node (fixed position network node) with remote (about 1500 meters) wireless communication ability is set, guaranteeing that the distance between adjacent two network nodes is not more than under the prerequisite of 600-800 rice, do not turn round for those public bus networks, too near again apart each other simultaneously crossroad can not be provided with network node.Simultaneously, on each bus, a same wireless micro-power transceiver (moving target) also is installed, on each bus stop, closely (about 30 a meters) platform communication module is installed, and the platform communication module links with the platform display device by wired mode, by wireless mode and moving target, and the fixed position network node links to each other.Can communicate by wired or wireless mode between the fixed network node, when using wireless mode, can use Zigbee network service management software to manage.Here need to prove: because the platform proximity communication module, and the difference between the network node, it mainly is the difference of transmitting power, thereby, the platform communication module can be received from network node at a distance, or the signal sent of moving target (bus), and moving target is only leaving in the 30 meters distances in station, just can receive the signal that the platform communication module is sent.
When bus is stopped certain public transport platform, moving target will be received the code signal of this platform that this platform communication module is sent, and the time of this platform stopped in record, and by being installed in the fixed position network node of crossroad, with these information, the information that comprises the number of getting on or off the bus in case of necessity passes toward control centre, and the place ahead platform.When bus travels between two crossroads that are provided with network node, these two network nodes receive the signal from bus, and corresponding signal strength signal intensity indication, utilize prior test at the scene to obtain, the relation of the signal strength signal intensity that position of bus and these two network nodes are received, we can be easy to obtain the particular location of bus between these two crossroads, pass to each station, the place ahead that vehicle is about to arrival by network then.
The field measurement effect: for fear of the mistake that may occur, before formally reinstating navigation system, also need actual steering vehicle, the actual motion circuit along public transit vehicle carries out physical location and signal strength signal intensity, or the measurement of critical transmitting power relation.
The optimization of system in the layout of real network, is guaranteeing that transport network communication is reliable, and navigation system under the situation, according to concrete environmental condition, can increase and decrease the quantity of network node simply accurately fully, and the position is adjusted, to reach optimum efficiency.
In the present case, the frequency range that transmitting set uses is the free frequency range of 2.4Ghz, adopts the direct sequence spectrum spread communication mode, omnidirectional transmitter antenna.
Financial cost is adjusted: if 20 buses are arranged on this circuit, two-way 50 stations interior, need about 100 wireless micro-power transceiver together with the circuit network node altogether.Add computer system, software etc., the cost of whole navigation system are no more than 200,000 yuan.Compare the existing GPS navigation system that is used for intelligent bus, this navigation system is in practical application, and is reliable and practical more; Economically, not only greatly reduce the hardware and the installation cost of system, and, owing to do not need to use existing mobile communications network, thereby the Internet utilization fee of having avoided existing GPS navigation system will pay in every month.
Claims (4)
1. a wireless micro-power network localization method is used for wireless micro-power network positioning system, it is characterized in that, described method comprises the steps:
A. set up writing to each other of network node and moving target;
B. by field measurement, set up in the locating area, corresponding to Q network node, the different fingerprint characteristics that the individual critical transmission power level of the Q of moving target is formed are with the one-to-one relationship of moving target diverse location in locating area;
C. by changing the transmitting power of moving target, find out corresponding to this Q network node, the common fingerprint characteristic of forming of moving target different critical transmission power level, again according to storing by field measurement in advance in the database, corresponding to this Q network node, the critical transmitting power fingerprint characteristic of moving target is with the one-to-one relationship of moving target diverse location in locating area, determine the position of moving target, at this moment Q 〉=1.
2. wireless micro-power network localization method according to claim 1, it is characterized in that, described wireless micro-power network positioning system comprises the network node of the wireless micro-power transceiver composition with fixed position, the control centre's computer system that links to each other with described network node, the moving target of wireless micro-power transceiver is installed, be connected by communication between described network node and the moving target, between described network node and the control centre's computer system, the mode by wireless or wire communication connects; Described control centre computer system stores has the address of network node, the identity code identifying information of moving target, and out of Memory and the network management software relevant with moving target location; Described wireless micro-power transceiver is by having single reception, or single emission function, or the integrated single-chip transceiver of height that reception and emission function have both simultaneously constitutes; Described network is a fixer network, is again an information transmission network, moving target just can be directly by this network and control centre's computer system communicate.
3. wireless micro-power network localization method according to claim 2, it is characterized in that, the transmitting power of all wireless micro-power transceivers in the described wireless micro-power network positioning system, on the international free frequency range of 2.4G ISM, be not more than 100mW, on other frequency ranges, remove and satisfy country the power use restriction on the relevant frequency range, be no more than 1W.
4. according to claim 2 or 3 described wireless micro-power network localization methods, it is characterized in that the employed frequency of described wireless micro-power transceiver is the international free frequency range of 2.4G ISM, and has adopted the direct sequence spectrum spread communication technology.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200910259930A CN101795467A (en) | 2006-11-02 | 2006-11-02 | Wireless micropower network positioning system and positioning method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200910259930A CN101795467A (en) | 2006-11-02 | 2006-11-02 | Wireless micropower network positioning system and positioning method thereof |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNA2006100221777A Division CN101175292A (en) | 2006-11-02 | 2006-11-02 | Wireless micro-power network positioning system and locating method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN101795467A true CN101795467A (en) | 2010-08-04 |
Family
ID=42587841
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200910259930A Pending CN101795467A (en) | 2006-11-02 | 2006-11-02 | Wireless micropower network positioning system and positioning method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101795467A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105388447A (en) * | 2014-08-28 | 2016-03-09 | 三星电子株式会社 | Mobile apparatus for generating beacon signal and service method using the same |
| CN105430744A (en) * | 2015-12-14 | 2016-03-23 | 广州广电计量检测股份有限公司 | Positioning method and positioning system |
| CN108074424A (en) * | 2016-11-18 | 2018-05-25 | 天津嘉深保科技发展有限公司 | A kind of Technological research network communication locator |
-
2006
- 2006-11-02 CN CN200910259930A patent/CN101795467A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105388447A (en) * | 2014-08-28 | 2016-03-09 | 三星电子株式会社 | Mobile apparatus for generating beacon signal and service method using the same |
| CN105430744A (en) * | 2015-12-14 | 2016-03-23 | 广州广电计量检测股份有限公司 | Positioning method and positioning system |
| CN105430744B (en) * | 2015-12-14 | 2020-03-24 | 广州广电计量检测股份有限公司 | Positioning method and positioning system |
| CN108074424A (en) * | 2016-11-18 | 2018-05-25 | 天津嘉深保科技发展有限公司 | A kind of Technological research network communication locator |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101175292A (en) | Wireless micro-power network positioning system and locating method thereof | |
| US8111153B2 (en) | Apparatus and method for providing position information and gathering information using RFID | |
| KR101049603B1 (en) | System and method of deciding the realtime location of mobile station using a RFID and method of setting up wireless repeater therefor | |
| CA2677882C (en) | A signal-comparison based location-determining method | |
| CN103033180B (en) | A kind of accurate Position Fixing Navigation System of indoor vehicle and method thereof | |
| CN101795466A (en) | Wireless micropower network positioning system and positioning method thereof | |
| EA000571B1 (en) | System for displaying position of mobile terminal | |
| CN101385382A (en) | System and methods for direction finding using a handheld device | |
| CN107333276A (en) | WiFi location fingerprint localization methods based on weighted chi-square distance | |
| CN103199898A (en) | Position identification and guide method based on bluetooth and two-dimension code | |
| CN102223706A (en) | Mobile positioning service system | |
| KR20080010717A (en) | System for location announcing using mobile terminal which has rfid-reader and rfid-tag having cadastral position information and method thereof | |
| CN101795467A (en) | Wireless micropower network positioning system and positioning method thereof | |
| CN101795486B (en) | Wireless micropower network positioning system and positioning method thereof | |
| JP3458826B2 (en) | Position calculation method, position calculation device, and mobile terminal | |
| WO2008054071A1 (en) | Apparatus and method for providing position information and gathering information using rfid | |
| KR101081426B1 (en) | Uses a both direction communication information integrated management system | |
| CN105929432A (en) | Hybrid positioning method, positioning terminal, and hybrid positioning system | |
| CN101795487A (en) | Wireless micropower network positioning system and positioning method thereof | |
| CN101795488A (en) | Wireless micropower network positioning system and positioning method thereof | |
| Jeon et al. | Smart parking system based on an ultrasonic sensor and bluetooth low energy in the internet of things | |
| Mishra et al. | A Novel and Cost Effective Approach to Public Vehicle Tracking System | |
| CN109462822A (en) | A kind of vehicle is accurately positioned the control system and control method of component | |
| CN101795489A (en) | Wireless micropower network positioning system and positioning method thereof | |
| CN114867088A (en) | Method and device for automatically reducing power consumption of satellite positioning mobile communication terminal |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C12 | Rejection of a patent application after its publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20100804 |